Perhaps you should try some spelling variations:
cach thuc » anh thuc, cac thu
hieu van » hieu va, thien van, lieu va
hanh tai » thanh tai, hang tai, han tai
tu cach » tu cac
tai cua » thai cua, tai cuc, tri cua
va hanh » van hanh, va thanh, va danh
cao duc » dao duc, cao suc, giao duc
hieu ve » hieu va
nang xa » nang x, lang xa, nang ma
tang ma » mang may, tang van
cua tre » cua te, cuu tre, cua triet

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: tu cach thuc ((nang xa) or (tang ma)) hoi. ((hieu ve) OR (hieu van)) cao duc va hanh tai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu cach thuc ((nang xa) OR (tang ma)) hoi. ((hieu ve) OR (hieu van)) cao duc va hanh tai cua tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu cach thuc ((nang xa) or (tang ma)) hoi. ((hieu ve) OR (hieu van)) cao duc va hanh tai cua tre*".